Mongo driver ideas

util.clj

(defn- normalize-details [details]
  (let [{:keys [dbname host port user pass ssl authdb tunnel-host tunnel-user tunnel-pass additional-options]
         :or   {port 27017, pass "", ssl false}} details
        ;; ignore empty :user and :pass strings
        user             (when (seq user)
                           user)
        pass             (when (seq pass)
                           pass)
        authdb           (if (seq authdb)
                           authdb
                           dbname)]
    {:host               host
     :port               port
     :user               user
     :authdb             authdb
     :pass               pass
     :dbname             dbname
     :ssl                ssl
     :additional-options additional-options}))

(defn- srv-connection-info
  "Docstring goes here"
  [{:keys [host port user authdb pass dbname ssl additional-options]}]
  (let [conn-opts (connection-options-builder :ssl? ssl, :additional-options additional-options)
        authdb    (if (seq authdb)
                    authdb
                    dbname)
        conn-str  (format "mongodb+srv://%s:%s@%s/%s" user pass host authdb)]
    {:type :srv
     :uri (MongoClientURI. conn-str conn-opts)}))

(defn- normal-connection-info
  "Docstring goes here"
  [{:keys [host port user authdb pass dbname ssl additional-options]}]
  (let [server-address                   (mg/server-address host port)
        credentials                      (when user
                                           (mcred/create user authdb pass))
        ^MongoClientOptions$Builder opts (connection-options-builder :ssl? ssl, :additional-options additional-options)]
    {:type           :normal
     :server-address server-address
     :options        (-> opts .build)}))

(defn- fqdn?
    "A very simple way to check if a hostname is fully-qualified:
   Check if there are exactly two periods in the name."
    [host]
    (= 2 (-> host frequencies (get \.))))

(defn- details->mongo-connection-info [{:keys [host], :as details}]
  ((if (fqdn? host)
     srv-connection-info
     normal-connection-info) details))

(defmulti ^:private connect
  "Connect to MongoDB using Mongo `connection-info`, return a tuple of `[mongo-client db]`, instances of `MongoClient`
  and `DB` respectively."
  {:arglists '([connection-info])}
  :type)

(defmethod connect :srv
  [{:keys [^MongoClientURI uri]}]
  (let [mongo-client (MongoClient. uri)]
    (if-let [db-name (.getDatabase uri)]
      [mongo-client (.getDB conn db-name)]
      (throw
       (IllegalArgumentException.
        (str (trs "No database name specified in URI. Monger requires a database to be explicitly configured.")))))))

(defmethod connect :normal
  [:keys [server-address options]]
  (let [do-connect   (partial mg/connect server-address options)
        mongo-client (if credentials
                       (do-connect credentials)
                       (do-connect))]
    [mongo-client (mg/get-db mongo-client dbname)]))

(defn -with-mongo-connection
  "Run `f` with a new connection (bound to `*mongo-connection*`) to `database`. Don't use this directly; use
  `with-mongo-connection`."
  [f database]
  (let [details (database->details database)]
    (ssh/with-ssh-tunnel [details-with-tunnel details]
      (let [connection-info   (details->mongo-connection-info (normalize-details details-with-tunnel))
            [mongo-client db] (connect connection-info)]
        (log/debug (u/format-color 'cyan (trs "Opened new MongoDB connection.")))
        (try
          (binding [*mongo-connection* db]
            (f *mongo-connection*))
          (finally
            (mg/disconnect mongo-client)
            (log/debug (u/format-color 'cyan (trs "Closed MongoDB connection.")))))))))